<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">
   <template id="aaa">我是谁</template>
</div>

<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js">
</script>
<script>
    let login={
        template:"#aaa"
    }
    const app=new Vue({
       el:"#app",
       data:{},
       methods:{

       },
       components:{
           login
       }
    });
</script>
</body>
</html>